JPH04312683A - Deformation controller for construction by introducing variable pre-stress - Google Patents

Abstract

PURPOSE:To control deformation caused by bending and rotation and to control defor mation of the whole construction by introducing variable pre-stress in a vertical direc tion of the construction, and controlling its magnitude. CONSTITUTION:Output variable jacks B are mounted to the lower ends of outside columns (a) on both sides of a construction A, and each of the jacks B is connected to one end of each of tension members T and T'. After that, the other end of each of the tension members T and T' is connected to the upper end of each of the outside columns (a). Then, the tension member T is introduced to the tension side of the construction A having bending and rotating deformation caused by an earthquake load and wind load, etc. Successively, the opposite tension member T' is released or eliminated, the tension side column is used as the compressed side column and vice versa by a vibration phenomenon of the construction A. Operations of introduction and release are alternately made at both outside columns (a) of directions receiving the bending and rotation between the tension members T and T', and constant damping action is always provided without depending on amplitude. According to the constitution, vibration of the construction A having bending and rotating deformation can be effectively reduced with a simple function.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for controlling the deformation of structures such as tower-like structures and skyscrapers.

0002

[Prior Art] When a wind load or an external seismic force acts on a structure, the structure shakes. Figure 10 shows the deformation state of a tower-shaped, high-rise structure. There are deformations etc. The present invention relates to a deformation control device for structures such as tower-like structures and skyscrapers that are subject to significant bending and rotational deformation.

[0003] When a fluctuating external force such as an earthquake load or a wind load acts on these structures, the structures shake. Conventionally, various mechanisms have been proposed to reduce this, and all of these use the viscous damping effect of the liquid as a deterrent force for vibration.Due to their characteristics, when the amplitude is small, the damping effect is small, and the damping effect is small. The energy generated is proportional to the square of the amplitude. (See FIG. 8) In the figure, p indicates a small deformation region, q indicates a large deformation region, and the deformation restraining force f is proportional to the deformation δ.

A structure deformation control mechanism has been proposed in which a prestress P0 is introduced on the tension side of a structure undergoing bending or rotational deformation. (See FIG. 4) This is because bending and rotational deformation is caused by the elongation of the tension side column and the contraction of the compression side column, so the introduced prestress P0 is intended to reduce the bending and rotational deformation.

[0005]

[Problem to be Solved by the Invention] In the former case, the restoring force characteristics when a viscous damping mechanism is provided in a part of the frame of a structure are schematically shown in FIG. (damping) is proportional to the deformation speed and deformation amplitude, and the deformation speed is proportional to the deformation amplitude, so the effect of amplitude attenuation is 2 times the deformation amplitude.
The effect decreases proportionally to the power of the power, so the effect is lost in small deformation regions.

In the latter case, as shown in FIG. 4, when prestress is applied to the column on the tension side to reduce the bending and rotational deformation of the structure, after 1/2 cycle due to the vibration phenomenon of the structure. , the column at this position becomes a compression side column, and if prestress is continued to be introduced as shown in FIG. 5, the bending and rotational deformation of the structure will increase on the contrary. The present invention has been proposed in view of the problems of the prior art described above, and its purpose is to adjust the magnitude of the prestress force introduced in the vertical direction of the structure to prevent bending and rotation. The object of the present invention is to provide a structure deformation control device that can control deformation and control deformation of the entire structure.

[0007]

[Means for Solving the Problems] In order to achieve the above object, a structure deformation control device by introducing prestress according to the present invention is provided at both upper and lower ends or in a portion of a shaft member of a structure where bending deformation and rotational deformation are predominant. By connecting tension members across the entire structure, prestress is applied through the tension members in the direction of suppressing deformation of the structure, and when unnecessary, the prestress is released or reduced to a required value. It is configured as follows.

[0008]

[Operation] Since the present invention is constructed as described above,
Only when a tensile force is applied to the shaft member of a structural material and the coaxial member is elongating, prestress is introduced by tension members placed at both the upper and lower ends of the coaxial member or partially to prevent deformation of the structure. In other cases, by releasing the prestress or reducing it to a predetermined value, it is possible to always provide a constant damping effect regardless of deformation or amplitude.

[0009]

[Embodiment] Fig. 1 shows an embodiment of the present invention, in which variable output jacks B are attached to the lower ends of the outer columns a on both sides of the structure A, and tension members are connected at one end to each jack B. T,
The other end of T' is connected to the upper end of the column a. In addition, when the column a is box-shaped or cylindrical, the tension material T can be provided in the internal space of the column a.

As shown in FIG. 3(a), a prestress P0 is applied to the tensile material T on the tension side of the structure A, which is bent and rotationally deformed due to earthquake loads, wind loads, etc. The prestress introduced into the tendon T' on the opposite side is released or reduced to a certain value, and then, due to the vibration phenomenon of structure A, after 1/2 cycle, the column on the tension side becomes a column on the compression side, and the column is compressed. The side pillars are tension side pillars, so they are shown in Figure 3 (
As shown in b), a prestress P0 is introduced into the tendon T', the prestress of the tendon T is released or reduced to a certain value, and the above operations are performed alternately on both outer columns in the direction of bending and rotation. By doing so, bending and rotational deformation of the structure A can be reduced compared to the case where such control is not performed. This is schematically expressed in the form of restoring force characteristics as shown in FIG. Figure 6 shows a case where prestress is introduced only when a tensile force is applied to the column and the column is elongating, and other prestresses are released, but regardless of the force acting on the column, the column is If prestress is introduced only when it is elongating, and released in other cases, the result will be as shown in Fig. 7.

On the other hand, in the conventional case where a viscous damping mechanism is incorporated into a part of the frame of a structure, its restoring characteristics are schematically shown in FIG. 8, and the deformation control according to the present invention is shown in FIG. The notable difference from the restoring characteristic diagram of the device is that in the conventional technology, energy consumption (damping) is proportional to the deformation speed and deformation amplitude, and the deformation speed is proportional to the deformation amplitude, so the vibration damping effect is proportional to the deformation amplitude. On the other hand, according to the present invention, the amplitude attenuation effect is proportional only to the deformation amplitude, so the effect is lost in small deformation areas because it decreases in proportion to the square of the deformation. This is a point where it works effectively. Further, since the damping effect is shown by the shaded area in FIGS. 8 and 9, it is advantageous in that a damping effect 4/π times can be expected for the same increase in resistance force (restoring force).

FIG. 2 schematically shows the variable output jack, in which a piston c is slidably fitted into a cylinder b fixed to the foundation via an anchor bolt C, and the rod of the piston c is A tendon T is connected to the cylinder b via a joint d, and the lower part of the piston c in the cylinder b has a cavity e,
Alternatively, it is formed as an oil chamber that freely flows in and out, and a jack pressure chamber 1 is formed above the piston c. A high pressure side check valve 2, a low pressure side check valve 3, a high pressure side lid pressure chamber 4, a low pressure side lid pressure chamber 5, a high pressure side check valve 6, and a low pressure side check valve 7 are connected to the cylinder b. 8. In the figure, 9 is an auxiliary pump, and 10 is an oil tank. Next, its operation will be explained. (a) First, use the auxiliary pump 9 to raise the internal pressure of the high-pressure side lid pressure chamber 4 to PH and the internal pressures of the low-pressure side lid pressure chamber 5 and the jack pressure chamber 1 in cylinder b to PL. (b) Structure A is bent by earthquake load and wind load,
When rotational deformation is about to occur, prestress TH is generated in the tendon T. (c) When the deformation progresses further and the pressure in the jack pressure chamber 1 reaches PH + ΔP, the hydraulic pressure in the jack pressure chamber 1 is released to the high pressure accumulator chamber 4 side by the action of the check valve 6, and the pressure in the jack pressure chamber 1 is always maintained at P
~PH + ΔP. Therefore, the tension of the tendon T is also maintained at a substantially constant value TH. The pressure in the high-pressure side pressure accumulation chamber 4 is maintained at a constant value by a release valve 2 configured to open when P>PH +ΔP, and excess oil is discharged to the low-pressure side pressure accumulation chamber 5. In addition, the pressure in the low-pressure side pressure storage chamber 5 is maintained at a constant value PL by the release valve 3, which is configured to open when P>PL +ΔP.
The excess oil is then discharged into the oil tank 10. (
d) When the deformation of the structure reaches its maximum point, the structure begins to deform in the opposite direction due to the restoring force. At this time, the pressure inside the jack pressure chamber 1 is reduced and the pressure is about to become negative, but the check valve 7
The pressure is maintained at low pressure PL by the inflow of oil from PL. Therefore, the tendon T has a low prestress TL (TL < TH and TL
(approximately 0) will be effective. (d)
The oil in the low-pressure side pressure storage chamber 5 is replenished from the high-pressure side pressure storage chamber 4 and, if insufficient, from the auxiliary pump 9.

However, in actual bending and rotational deformation of structures, there is always a tension side and a compression side, so (e)
The operation of the auxiliary pump 9 described in 1 is almost unnecessary. In addition, in the case of vibrations that last for a long time, such as wind vibrations, the pressure conditions (PH, PL) will naturally change after several vibrations.
Since this holds true, the auxiliary pump 9 is hardly needed except for supplementing the insufficient amount of oil in the step (a).

[0014]

Effects of the Invention As described above, the structure deformation control device according to the present invention connects tendons at both upper and lower ends or partially over a shaft member of a structure where bending deformation and rotational deformation are predominant,
By applying prestress in the direction of suppressing the deformation of the structure through the tension material, and at the same time releasing the prestress when unnecessary or reducing it to a desired value, the structure can be bent with a simple mechanism. It is possible to effectively reduce the vibration of structures that are prone to rotational deformation, and unlike conventional mechanisms such as TMD, there is no need to place heavy objects on top of the structure, and unlike conventional mechanisms, it is possible to reduce There are no design restrictions on periodic, large-amplitude vibrations, and it can be applied in any situation.

Furthermore, although a control device using a viscous damping mechanism has a reduced effect in a small amplitude region, the present invention eliminates this problem.

[Brief explanation of drawings]

FIG. 1 is an elevational view showing an embodiment of a structure deformation control device by introducing variable prestress according to the present invention.

FIG. 2 is a schematic diagram of a variable output jack mechanism.

[Figure 3] An explanatory diagram showing the state in which prestress is alternately introduced and released on both sides of a structure subjected to bending. (a) shows the case where prestress is introduced to the column on the left, and (b) shows the case where prestress is introduced to the column on the right. shows.

FIG. 4 is an explanatory diagram showing a state in which prestress is applied to the tension side column.

FIG. 5 is an explanatory diagram showing a state in which prestress is applied to the compression side column.

FIG. 6 is a restoring force characteristic diagram when prestress is introduced only when tensile force is applied to the column and the column is elongating, and prestress is released in other cases.

FIG. 7 is a restoring force characteristic diagram when prestress is introduced when the column is deformed in the direction of extension, and released in other cases, regardless of the force acting on the column.

FIG. 8 is a diagram of restoration characteristics by a viscous damping mechanism.

FIG. 9 is a restoration characteristic diagram according to the present invention.

FIG. 10 is an explanatory diagram showing deformation of a structure.

[Explanation of symbols]

A Structure B. Variable output jack T Tensile material T' Tensile material a Outer pillar

Claims (1)

[Claims] Claim 1: Tensile members are connected to both upper and lower ends or partially of a shaft member of a structure where bending deformation and rotational deformation are predominant, and the structure is directed in a direction that suppresses deformation of the structure through the tension members. A device for controlling deformation of a structure by introducing variable prestress, characterized in that it is configured to apply prestress and, when unnecessary, release or reduce the prestress to a required value.